diff --git a/include/cyclone/runtime-main.h b/include/cyclone/runtime-main.h
index bdc098e9..7fb99c6a 100644
--- a/include/cyclone/runtime-main.h
+++ b/include/cyclone/runtime-main.h
@@ -28,8 +28,12 @@ static void Cyc_heap_init(long heap_size)
   printf("main: Allocating and initializing heap...\n");
 #endif
   Cyc_heap = gc_heap_create(heap_size / 2, 0, 0);
-  Cyc_num_mutators = 10; // TODO: alloca this using a vpbuffer, or maybe another type of data structure
-  Cyc_mutators = malloc(sizeof(gc_thread_data *) * Cyc_num_mutators);
+  // TODO: alloca this using a vpbuffer, or maybe another type of data structure??
+  // Will need this list for later use, but only by the collector thread. so it would be
+  // nice if there was a way to allocate mutators that avoids expensive synchronization...
+  // need to think on this when adding thread support, after upgrading the collector
+  Cyc_num_mutators = 1; 
+  Cyc_mutators = calloc(Cyc_num_mutators, sizeof(gc_thread_data *));
 }
 
 #endif /* CYCLONE_RUNTIME_MAIN_H */